The use of occlusive devices in the vascular system and in other systems of the body, e.g., genito-urinary and biliary systems, is known. In the vasculature, a physician may apply a vaso-occlusive device using endovascular techniques to a selected site to cause the site to fill with thrombus. The occlusion often changes in composition to a more collagenous composition over time.
A variety of maladies may be treated in this way. For instance, an occlusion may be used to limit bleeding due to vascular accidents such as strokes or to fill abnormal vascular cavities such as aneurysm or to limit the flow of blood to an anomalous anatomical region, e.g., a tumor or one of the extraneous sites in a multi-focal electrical arrhythmia.
Occlusive devices and materials used in such service are typically of two types: solids and reactive fluids. The class of solid-occlusive devices includes an eclectic variety of materials: hog hair, polyvinyl alcohol beads, collagen beads, latex beads, and silk or rayon fibers. Devices such as coils or balloons are also known and used.
Cyanoacrylate glues are occasionally applied as vaso-occluding materials. These are not type-approved and a specific approval must be determined for each use. Glues are difficult to place within the vasculature and although they create excellent occlusions, they may do so at a site downstream of the desired site.
The most practical of these devices and methods from both a precision placement aspect and an effectiveness aspect are vaso-occlusive coils with or without added thrombogenic fibers. An early endovascular coil device is found in Ritchart et al., U.S. Pat. No. 4,994,069. These devices are lengthy in comparison to the inventive devices described here and rely on the volume of the coil and the secondary shape of the coil after it exits the delivery catheter for defining the bulk of the resulting occlusion.
A variation of the vaso-occlusive coils are shown in U.S. Pat. Nos. 5,226,911 and 5,304,194 to Chee et. al. Those patents show the use of longer vaso-occlusive coils having attached fibrous elements which are looped from place-to-place along the coils.
A further variation is shown in U.S. Pat. No. 5,382,259, to Phelps et. al. Phelps et al. shows a coil having a braided fibrous covering on the exterior of the coil. The braid is placed on the coil for the purpose of increasing the assembly's tendency to produce thrombus.
Target Therapeutics, Inc. owns other pending patent applications relating to vaso-occlusive devices including "FIBERED MICRO VASO-OCCLUSIVE DEVICES" by Sepetka et al, Ser. No. 08/566,608, filed Dec. 4, 1995 and "STRETCH RESISTANT VASO-OCCLUSIVE COILS" by Gia et al, Ser. No. 08/607,593, filed Feb. 27, 1996. Neither describes the devices claimed herein.
None of these devices are soft-ended, vaso-occlusive devices having short binders holding significantly longer fibers.
Other occluding devices having a plug-like form are known.
U.S. Pat. No. 5,095,917, to Vancaille, shows a transuterine technique for sterilization of females using a biodegradable plug. The plug is used in conjunction with the destruction of a mucous layer to form a site for inflammation and, upon healing, form an occlusion. No fibers are used in conjunction with the plug.
U.S. Pat. No. 5,192,301, to Kamiya et al., shows a closing plug which is to be delivered percutaneously to close somatic wall defects such as arterial septal defects (ASD). The plug is preferably of a shape memory polymer and has shape involving a cone at one end and a flange at the other. Again, fibers are not involved in the structure of the device.
U.S. Pat. No. 5,443,478, to Purdy, shows a multi-element vascular device having an anchoring element and a lead element connected by fibers. The anchoring element is typically a coil forming a circular element. After deployment of the device from a delivery catheter, the anchoring element secondary shape is approximately the size of the vessel to be occluded. The typically somewhat smaller lead element is also often a coil but is depicted to be of a smaller size than the anchoring element. The fibers are not aligned with the coil upon deployment of the device, however.
Japanese Kokai 4-312454 shows an occlusive device which appears to have multiple magnetic portions. The magnetic portions are shown to be square in FIG. 1 and spherical in FIG. 3 of the publication. The magnetic portions do not appear to act as clasps on the fiber.
None of the disclosed devices are similar to the inventive vaso-occlusive device.